Measuring light bouncing off a window to hear conversations, using millimeter waves to see through walls, taking photos from space, and planes that could fly themselves were all the realm of science fiction at one point - while in the hands of intelligence agencies.
In most cases it's their ability to spend money to build large teams, the complete scale of operations (XKeyscore comes to mind), and the care they care which is where things like the NSA dominate vs the average ability of the best hacker. But their advantage is only rarely in the individual technological leaps, which industry has no match of or well informed technical experts are unaware of, like the things you reference.
Massive antenna arrays and SIGINT satellites have massive funding and decades of history, and they've already shown interest in tracking literally everything else [1]
This isn't some star trek type of thing, this is a "would the USG dump enough money into SIGINT to implement it?"
I'm very confident the technology exists to roughly track specific locations of interest for specific devices if not more.
I understand people may disagree but it would be foolish to assume it's beyond the realm of possiblity.
[0] https://space.stackexchange.com/questions/55143/is-it-possib...
[1] https://www.aerosociety.com/news/eavesdropping-from-space/
Laser microphones are old too. Clear and Present Danger features the use of a laser mic and that was written in 1989.
Sure it is. The iPhone can do that right now with emergency SOS.
What's less feasible is having enough of these at good positions overhead of a single cell phone to multi-laterate it's position using shared timestamps on the downlinked spectrum from multiple satellites.
I think it's entirely feasible with the budget of a medium space services corporation that can launch 21 satellites.
> Cellular signal from a personal cellphone isn't strong enough to register at satellite altitude.
This isn't entirely true. A primary limiting factor is the frequency-specific gain of satellites' antenna arrays. With a big enough antenna and fast and sensitive enough ADCs, much more is possible. Sifting through TD-SCDMA is the fun part.
Despite the headline, the system does NOT track individual cellphones or GPS receivers. Cellular signal from a personal cellphone isn't strong enough to register at satellite altitude. The same goes for non-milspec walkie-talkies.